TERMS USED IN BIOPROCESS ENGINEERING

The terminologies used in BioProcess Engineering (BPE) sometimes mean differently. I have collected a few important terms from ASME BPE and other BP literatures.

Aseptic: Free of pathogenic microorganism

Aseptic processing: Operating in a manner that prevents contamination of the process.

Autogenous weld: A weld made by fusion of the base material without the addition of filler.

Automatic welding: Welding with equipment that performs the welding operation without adjustment of the controls by a welding operator. The equipment may or may not perform the loading and unloading of the work.

Bioprocessing Equipment: Equipment, systems, or facilities used in the creation of products utilizing living organisms.

Break: A discontinuity in the face of a fitting.

Burn-through: Excessive melt-through or a hole through the root bead of a weld.

Burr: Excess material protruding from die edge typically resulting from operations such as cutting or facing.

Butt joint: A joint between two members lying approximately in the same plane.

Cavitation: A condition of liquid flow where, after vaporization of the liquid, the subsequent collapse of vapor bubbles can produce surface damage.

Certification: Documented testimony by qualified authorities that a system qualification, calibration, validation, or revalidation has been performed appropriately and that the results are acceptable.

cGMPs: Current Good Manufacturing Practices. Current design and operating practices developed by the pharmaceutical industry to meet FDA requirements

Chromatography: The purification of substances based on chemical, physical and biological properties of the molecules involved.

Clean: Free of dirt, residues, detergents or any contaminants that may affect or adulterate the product or process

Clean-in-Place (CIP): Internally cleaning a piece of equipment without relocation or disassembly. The equipment is cleaned but not necessarily sterilized. The cleaning is normally done by acid, caustic, or a combination of both, with Water-for-Injection (WFI) rinse.

Clean steam: Steam free from boiler additives that may be purified, filtered, or separated. Usually used for incidental heating in pharmaceutical applications.

Cloudiness: The appearance of a milky white hue across some portion of a surface resulting from the electro polish process.

Cluster porosity: Porosity that occurs in clumps or clusters.

Concavity: A condition in which the surface of a welded joint is depressed relative to the surface of the tube or pipe. Concavity is measured as a maximum distance from the outside or inside diameter surface of a welded joint along a line perpendicular to a line joining the weld toes.

Consumable insert: A ring of metal placed between the two elements to be welded that provides filler for the weld, when performed with fusion welding equipment. A consumable insert can also be used for the root pass in a multiple pass weld with the addition of filler wire (also called insert ring).

Convexity: A condition in which the surface of a welded joint is extended relative to the surface of the tube or pipe. Convexity is measured as a maximum distance from the outside or inside diameter surface of a welded joint along a line perpendicular to a line joining the weld toes.

Cracks: Fracture-type discontinuities characterized by a sharp tip and high ratio of length and width to opening displacement. A crack may not be detected

Dead Leg: An area of entrapment in a vessel or piping run that could lead to contamination of the product.

Fermentor (fermenter): A vessel for carrying out fermentation.

GMP facility: A facility designed, constructed, and operated in accordance with cGMP guidelines established by the FDA.

Hold-up volume: The volume of liquid remaining in a vessel or piping system after it has been allowed to drain.

Hygienic clamp joint: A tube outside diameter union consisting of two neutered ferrules having flat faces with a concentric groove and mating gasket that is secured with a clamp, providing a nonprotruding, recessless product contact surface.

Hydrotest: A pressure test of piping, pressure vessels or pressure containing parts, usually performed by pressurizing the internal volume with water at a pressure determined by the applicable code.

Inclusions: Particles of foreign material in a metallic matrix. The particles are usually compounds such as oxides, sulfides, or silicates, but may be any substance foreign to and essentially insoluble in the matrix.

Machine welding: Welding with equipment that performs the welding operation under the constant observation and control of a welding operator. The equipment may or may not perform the loading and unloading of the works.

Manual welding: Welding in which the entire welding operation is performed and controlled by hand.

Maximum working pressure: The pressure at which the system is capable of operating for a sustained period of time.

Maximum working temperature: The temperature at which the system must operate for a sustained period of time. The maximum working temperature should relate to the maximum working pressure and the fluids involved.

Orbital welding: Automatic or machine welding of tubes or pipe in-place with the electrode rotating (or orbiting) around the work. Orbital welding can be done with the addition of filler material or as a fusion process without the addition of filler.

Oxidation: The formation of an oxide layer on a metal surface. When oxidation occurs as a result of welding, it is visible as discoloration. The discoloration or heat tint produced by oxidation has been associated with it the onset of corrosion in stainless steel piping systems.

Passivation: A final treatment/cleaning process used to remove free iron or other anodic contaminants from the surfaces of corrosion-resistant steel parts such that uniform formation of a passive layer is obtained.

Pipe: Pipe size is determined by diameter and schedule. For bioprocessing equipment, pipe does not include tube.

Pressure rating: Pressure at which a system is designed to operate, allowing for the applicable safety factors.

Product contact surface: A surface that contacts raw materials, process materials and product.
Pure steam: Steam that is produced by a steam generator which, when condensed, meets requirements for Water-for-Injection (WFI).

Pyrogen: A fever-producing substance.

Sanitary (hygienic) weld: Generally considered to be a groove weld in a square butt joint made by the GTAW (or plasma) process as a fusion weld without the addition of filler material. A sanitary weld must be completely penetrated on the weld ID, with little or no discoloration due to oxidation, and be otherwise without defects that would interfere with maintenance in a clean and sterile condition.

Seal weld: A weld used to obtain fluid tightness as opposed to mechanical strength.

Self-draining: The elimination of all fluid from the system due to the force of gravity alone.

Slope: An inclination or deviation from the horizontal. A tube or pipe installed in the horizontal plane is said to slope if one end is positioned higher than the other.

Sparger: A device used to agitate, oxygenate, or aerate a liquid by means of compressed air or gas.

Steam In Place (SIP): The use of steam to sanitize or sterilize a piece of equipment without the use of an autoclave.

Sterile: Free from living organisms.

Sterility: the absence of all life forms.

System volume: Total volume of liquid in the system, including equipment, piping, valving, and instrumentation.

Tube: Tube is sized by its nominal outside diameter. For bioprocessing equipment, tube does not include pipe.

Validation: Establishing documented evidence that the system does what it purports to do.

Waviness: Undulations or rippling of the surfaces.

Weld joint design: The shape, dimensions, and configuration of the weld joint.